Back fall on soil pipe

Hi i was wondering if this is going to cause me a real headache in the future,

the soil pipe as it exits the wall, on the right hands side of the toilet, has a very small back fall, the spirit levels bubble is not quite center and if i lift the level about 1mm over half a metre, it becomes bang on.

I think when i cored the hole i didnt get it absolutely spot on.

i have put the toilet in and chucked a bucket of water down it, no leaks and the water in the toilet is at about the right level. However when i dismantled the pan connector a little bit of water came out.

Do you think this is going to drip or have a rubbish flush.

or am i worrying over nothing.

i think i have three options.
1. Do nothing.
2. Chip out the hole so the fall is right.
3. cut the pipe off flush to the wall put an extension in, then the back fall is only as long as the wall is deep, plus as the extension goes into the soil pipe it should be even less, than the depth of the wall, but then i have two potential joints opposed to the one.

A back fall is never a good idea &, in fact, does not comply with B Regs. You will undoubtedly get standing water & a potential for other “goodies” to lie in that section of the pipe which could lead to a blockage. You have easy access to clear, it’s very close to the w/c & if the section of pipe is fairly short, in reality, it’s likely to be self purging. If it’s a lot of hassle to rectify, I would be inclined to leave it but if it’s a new w/c install & subject to inspection, the BI may pick it up & ask you to fix it.